diff --git a/core/constants/network-port.go b/core/constants/network-port.go
index e4c6bad..7f930e1 100644
--- a/core/constants/network-port.go
+++ b/core/constants/network-port.go
@@ -14,13 +14,13 @@ const (
 
 var (
 	portTypeID = map[PortType]string{
-		PortTypeTCP: "TCP",
-		PortTypeUDP: "UDP",
+		PortTypeTCP: "tcp",
+		PortTypeUDP: "udp",
 	}
 
 	portTypeName = map[string]PortType{
-		"TCP": PortTypeTCP,
-		"UDP": PortTypeUDP,
+		"tcp": PortTypeTCP,
+		"udp": PortTypeUDP,
 	}
 )